• Korean Journal of Fisheries and Aquatic Sciences
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• v.48 no.2
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• pp.244-248
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• 2015

We explored the efficiency of natural antibacterial agents used to enhance the self-life and sensory properties of shucked and packed Pacific oyster Crassostrea gigas, which are in high demanded. First, we screened natural resources exhibiting antibacterial activity against food spoilage and pathogenic bacteria. Of theses, ignited oyster shell powder (IOS) and the natural food preservative, lactic acid bacteria fermented powder (LBF), were selected for further study considering the efficacy, mass production, and cost. The addition of 0.1% IOS (W/V) and 0.5% LBF (W/V) to shucked and packed oyster optimally extended the shelf-life without affecting the sensory evaluation. The results obtained in this study will provide a clue to enhance self-life in raw oyster products.

• Journal of Practical Agriculture & Fisheries Research
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• v.7 no.1
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• pp.81-89
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• 2005

The experiment was conducted to evaluate the effect of fruit skin spray of the lime fertilizer in 'Campbell Early' grapes. The T-N, P, K, Ca and Mg of fruit skin and cluster weight, berry weight, cluster length showed no difference between control and lime fertilizer. But soluble solids in fruit was reduced by fruit skin spray of liquid calcium fertilizer extracted from oyster shell after bagging(LCaB). The anthocyanin content of fruit skin was decreased by air-slaked lime(HCa) and LCaB treatment. Also, occurrence of fruit skin bloom was significantly reduced by HCa and oyster shell powder(OS-CaP) treatment. The berry firmness was significantly increased through liquid calcium fertilizer extracted from oyster shell(LCa) and HCa treatment. Conspicuously, berry elasticity was rather decreased by OS-CaP treatment. However, there was no difference of weight loss of fruit among treatments during room temperature storage.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.29 no.2
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• pp.79-86
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• 2023

In this study, poly(lactic acid) (PLA) and Poly(butylene-adipate-co-terephthalate) (PBAT) composite films containing calcined oyster shell powder (OSP) were evaluated for the applicability of antimicrobial packaging. PLA/PBAT-OSP composite films were prepared using twin-screw extruder. The OSP composite was incorporated into PLA/PBAT blend with different ratios (0, 1, 3, 5 and 10%) and the effect of OSP in the PLA/PBAT matrix was evaluated. The PLA/PBAT-OSP composite films were evaluated for properties using FT-IR, SEM, TGA, DSC, UTM, UV-vis, and Contact angle, as well as antimicrobial property was examined according to ISO 22196 - Antimicrobial Plastic Test. As OSP was added, it showed high antimicrobial activities for both Gram-positive (Staphylococcus aureus) and Gram-negative (Escherichia coli) bacteria. On the other hand, it was found that mechanical properties decreased as OSP was added. For the application of PLA/PBAT-OSP composite films as an antimicrobial packaging material, it is necessary to improve the dispersibility of OSP in the PLA/PBAT composite films and their physical properties at the same time.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.48 no.5
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• pp.596-603
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• 2015

This study investigated the effects of adding oyster shell powder (OSP) from Crassostrea gigas on the food quality of Chinese cabbage Kimchi (CCK). We monitored the changes in microbial levels, pH, acidity and sensory evaluation during the fermentation of CCK treated with various contents of OSP. The microbial assay showed that adding OSP to CCK inhibited the growth of viable cells, total coliforms, and lactic acid bacteria, with the greatest growth inhibition against lactic acid bacteria over the fermentation period. After fermentation for 18 days, the lactic acid bacterial counts in CCK treated with OSP (0.3%, 0.5% and 1%) were at least 1 log CFU/g lower than those of control CCK. In addition, the pH and acidity of CCK treated with OSP were lower than in control CCK over the fermentation period. The overall sensory evaluation of CCK with 0.3% OSP was better than that of control CCK after fermentation for 24 days. In conclusion, OSP treatment, especially 0.3% OSP, enhances the food quality and extends the self-life of CCK, while minimizing the detrimental effects on its sensory characteristics.

• Journal of Environmental Science International
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• v.27 no.9
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• pp.763-770
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• 2018

Bioremediation in situ is heavily dependent on the oxygenic environment which would privide the dwelling microorganism with sufficient oxygen. The situation could be easily resolved with supply of an Oxygen Releasing Compound (ORC). In this paper we prepared that sort of material out of oyster shell powder (mostly calcium carbonate) that prevails every shore areas of the country. We used two different oxidizing methods in the first step of the whole manufacturing process-conventional heating in a furnace and an ultrasound generator to obtain calcium oxide. Then that calcium oxide was further oxidized into calcium peroxide which may release oxygen under a moisturized condition. The oxygen releasing experiments were run to test the performance of our products, and to determine the gas kinetics during the experiments. Interestingly, calcium peroxide derived from ultrasound treatment was much more energy-effective as ORC than that from furnace heating although the heat derived process was better than that of ultrasound in terms of oxygen content and its releasing rate. We also found that most of the data collected from the gas releasing experiments fairly supported an ordinary $1^{st}$ order kinetics to oxygen concentration, which shaped a sharp discharge of oxygen at the very early moment of each test.

• Food Science of Animal Resources
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• v.34 no.3
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• pp.372-377
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• 2014

This study was conducted to evaluate the effects of oyster shell calcium powder (OSCP) as a substitute for phosphates in curing agent, on the quality of restructured pork ham. Restructured pork ham was processed under six treatment conditions: T1 (no additives), T2 (0.3% sodium tripolyphosphate), T3 (1.5% NaCl+0.5% whey protein), T4 (1.5% NaCl+0.5% whey protein+0.15% OSCP), T5 (1.5% NaCl+0.5% whey protein+0.3% OSCP), and T6 (1.5% NaCl+0.5% whey protein+0.5% OSCP). Addition of OSCP significantly increased the ash content and pH of restructured pork ham (p<0.05), but did not affect the cooking loss and water holding capacity values of restructured pork ham. Addition of OSCP had no effect on Hunter a and b surface color values of restructured pork ham, but did decrease the Hunter L surface color value (p<0.05). The addition of 0.5% OSCP showed significantly higher chewiness and springiness values of restructured pork ham, compared with the addition of phosphates (p<0.05). In conclusion, the addition of OSCP combined with low NaCl and 0.5% whey protein can be considered a viable substitute for phosphates in the curing agent, when processing restructured pork ham.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.36 no.6
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• pp.716-722
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• 2003

This study determined the optimum dosage for coagulation reactions of red tide organisms (RTO) using a combination of ignited oyster shell powder (10sp) and loess and examined the electrokinetic and rheological characteristics of their flocs. Two kinds of RTO, Cylindrotheca closterium and Skeletonema costatum, were sampled in Masan Bay and cultured in the laboratory. Coagulation experiments were conducted using various concentrations of IOSP, loess, IOSP+1oess, RTO, and a jar tester RTO cell numbers were counted for both the supernatant and RTO culture solution. The removal rates increased rapidly with increasing IOSP concentrations up to 50 mg/L and loess concentrations up to 800 mg/L. A removal rate of $100\%$ was reached at 400 mg/L of IOSP and 6,400 mg/L of loess. The highest increment $(16.7\%)$ of the rates of coagulation reaction occurred using both IOSP and loess (50+200 mg/L) in comparison with IOSP alone. The rate of coagulation reaction using both IOSP and loess (50+200 mg/L), $90.6\%,$ was similar to employing either IOSP of 150 mg/L or loess of 3,200 mg/L. All of the coagulation liquids for RTO, IOSP (200 mg/L), loess (200 ma/L), and IOSP+1oess (200+200 mg/L) revealed non-Newtonian fluid properties and therefore their shear rate vs. shear stress curves were non-linear. The coagulation liquids revealed elastic body properties at a lower shear rate increasing in the following order: RTO, IOSP (200 mg/L), loess (200 mg/L), and IOSP+1oess (200+200 mg/L. IOSP+1oess (200+200 mg/L) especially demonstrated plastic flow properties at a lower shear rate.

• Food Science of Animal Resources
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• v.43 no.2
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• pp.245-268
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• 2023

The effects of phosphate alternatives on meat quality in marinated chicken were investigated with the application of chilling and freezing. Breast muscles were injected with solution of the green weight containing 1.5% NaCl and 2% sodium tripolyphosphate (STPP) or phosphate alternatives. Treatment variables consisted of no phosphate [control (-)], 0.3% sodium tripolyphosphate [control (+)], 0.3% prune juice (PJ), 0.3% oyster shell, 0.3% nano-oyster shell, and 0.3% yeast and lemon extract (YLE) powder. One-third of the meat samples were stored at 4℃ for 1 d, and the rest of the meats were kept at -18℃ for 7 d. In chilled meat, a lower drip loss was noted for control (+) and YLE, whereas higher cooking yield in YLE compared to all tested groups. Compared with control (+), the other treatments except PJ showed higher pH, water holding capacity, moisture content, lower thawing and cooking loss, and shear force. Natural phosphate alternatives except for PJ, improved the CIE L^* compared to control (-), and upregulated total protein solubility. However, phosphate alternatives showed similar or higher oxidative stability and impedance measurement compared to control (+), and an extensive effect on myofibrillar fragmentation index. A limited effect was observed for C^*, h°, and free amino acids in treated meat. Eventually, the texture profile attributes in cooked of phosphate alternatives improved except for PJ. The results indicate the high potential use of natural additives could be promising and effective methods for replacing synthetic phosphate in chilled and frozen chicken with quality enhancement.

• Resources Recycling
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• v.6 no.3
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• pp.28-35
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• 1997

Adsorption properities of hcavy metals (Cd, Cu, Fe, Mn, Pb, Zn) and organic compounds (Trichloroethylene and T Tetrachroethy len려 on sh$\xi$1I( oyster and ark shell) were investigated using wat$\xi$r treatment matenals, The shell powder (m띠or C crystal structurc is calcium hydroxide) showed the preference adsorption for heavy metals in order of Mn > Zn > Fe > Cd > eu > P Pb. The high removal capacities of heavy metals arc helicved to be largely due to precipitation by foonation of metal c carhonat,잃 and hydroxides at high pH caused by the $Ca(OH)_2$ component of sl1ell, immobilizatIon of heavy metals in a solid I matrix by calcium‘ and fixation by insoluble organic materials in the oystcr and ark shell. The use of sh려I in water treatment h has the potential to bc benefIcial as a source of inexpensive matcrials‘ moreover, not only treatment of waste but also e environmcntal business including environmental-purification ceramics could be better off by utili낌ng high-valued waste and d developed puri'fication ceramics and media.

• Food Science of Animal Resources
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• v.43 no.2
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• pp.232-244
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• 2023

We investigated the effects of different phosphate replacements on the quality of ground pork products cured with sodium nitrite or radish powder to determine their potential for achieving clean-label pork products. The experimental design was a 2×5 factorial design. For this purpose, the ground meat mixture was assigned into two groups, depending on nitrite source. Each group was mixed with 0.01% sodium nitrite or 0.4% radish powder together with 0.04% starter culture, and then processed depending on phosphate replacement [with or without 0.5% sodium tripolyphosphate; STPP (+), STPP (-), 0.5% oyster shell calcium (OSC), 0.5% citrus fiber (CF), or 0.5% dried plum powder (DPP)]. All samples were cooked, cooled, and stored until analysis within two days. The nitrite source had no effect on all dependent variables of ground pork products. However, in phosphate replacement treatments, the STPP (+) and OSC treatments had a higher cooking yield than the STPP (-), CF, or DPP treatments. OSC treatment was more effective for lowering total fluid separation compared to STPP (-), CF, or DPP treatments, but had a higher percentage than STPP (+). The STPP (+) treatment did not differ from the OSC or CF treatments for CIE L^* and CIE a^*. Moreover, no differences were observed in nitrosyl hemochrome content, lipid oxidation, hardness, gumminess, and chewiness between the OSC and STPP (+) treatments. In conclusion, among the phosphate replacements, OSC addition was the most suitable to provide clean-label pork products cured with radish powder as a synthetic nitrite replacer.